I am not sure what the bear and mountain lion population is like around there, but I would only add a couple things. Keep the gun were you can get to it in a split second. Zipped in your pack could prove to be fatal. I would suggest also packing some Pepper spray also. Just a crucial as the gun is chosing a good defense hollow point round for it(anything but ball ammo). A good "cheap" defensive round you can afford to practice with is Winchester ranger "T" series. Good luck and have fun
PS. A few other non defense items depending on how secluded the trail is.
1.)Compass /Cheap Garmin GPS could come in handy also.
2.)SAS survival guide ($11 at amazon)
3.)Paracord 50ft
4.) LeD maglite mini 30 hours on 2 AA
5.) Army mess kit
6.) Good knife (Gerber LMF II, $65 amazon)
7.) Pill bottle with 200ft fishing line round around a qtip(use power drill), 5 fishhooks, few sinkers, cotton swabs and small firestarter(gobspark).
8.) Small first aid kit with alcohol swabs and blister medicine. Mosquito repellent depending ontime of the year.
You can fit most of that stuff in a small 7"x3" tupperware conainer. and besides the knife it will only weigh about a pound.